Publication:

Association between digestive function and sleep outcomes: a systematic review protocol

Background Digestive disturbances and sleep disorders frequently coexist and are increasingly recognized to share interconnected circadian, metabolic, inflammatory, and neuroendocrine pathways. The gut–sleep axis has emerged as a framework describing bidirectional interactions between gastrointestinal physiology, gut microbiota, and sleep regulation. Ayurveda presents a parallel systems-based perspective through the concepts of Agni (digestive capacity) and Nidra (sleep), emphasizing that impaired digestion and accumulation of Ama may contribute to disturbed sleep and systemic imbalance. This systematic review aims to synthesize available evidence evaluating the relationship between digestive function and sleep outcomes and to explore the underlying physiological and mechanistic pathways linking these processes.

Methods Human clinical and observational studies will form the primary evidence base, while experimental and animal studies investigating digestive–sleep mechanisms will be considered separately to support mechanistic interpretation and will not be included in quantitative synthesis. Literature searches will be conducted across MEDLINE, Embase, CENTRAL, Scopus, Web of Science, the AYUSH Research Portal, and Google Scholar, with citation tracking and screening of Ayurvedic postgraduate and doctoral dissertations, for studies published up to October 2025. Methodological quality will be independently assessed by two reviewers using the RoB-2 and ROBINS-I tools. Findings will primarily be synthesized narratively, with meta-analysis undertaken only if methodological and outcome homogeneity permit; heterogeneity will be assessed using the I² statistic and certainty of evidence evaluated using the GRADE approach.

Conclusions This review is expected to provide an integrative understanding of digestive–sleep interactions and inform future research and evidence-based clinical strategies. Trial registration: PROSPERO CRD420251178526.